Multi-stage locking system for selective release of a potential energy force to set a subterranean tool

Abstract

An actuation tool uses a lock that when released allows a moving magnet to move into position to repel another magnet. Alternatively a magnetic field can be triggered in a stationary magnet such as one delivered on wireline, for example, to accomplish tool actuation. The repelling force on the second magnet moves it away from a locking position to allow another lock to retract and release the stored potential energy, where the release of the potential energy creates kinetic energy to drive an actuation assembly to set the tool. In a preferred application the tool can be a liner hanger. The release device can be a selectively energized electromagnet or a solenoid that shifts at least one magnet into alignment with at least one second magnet so as to defeat the second magnet from effectively supporting dogs that retain the potential energy whose movement can set the tool.

I claim: 
     
       1. An actuation assembly for a subterranean tool, comprising:
 a mandrel supporting a final controlled element; 
 a first potential energy source associated with said mandrel; 
 a first detent assembly to selectively isolate said potential energy source from said final controlled element: 
 a second detent assembly selectively operable independently of said first potential energy source and said first detent assembly, said second detent assembly when selectively defeated by a first mechanical movement, thereafter, defeats said first detent assembly by a second mechanical movement to allow said first potential energy source to move said final controlled element. 
 
     
     
       2. The assembly of  claim 1 , wherein:
 said first detent assembly moves in an opposite direction than said second detent assembly. 
 
     
     
       3. The assembly of  claim 1 , wherein:
 said second detent assembly is selectively driven by a second potential energy source. 
 
     
     
       4. The assembly of  claim 3 , wherein:
 said second potential energy source is weaker than said first potential energy source. 
 
     
     
       5. An actuation assembly for a subterranean tool, comprising:
 a mandrel supporting a final controlled element; 
 a first potential energy source associated with said mandrel; 
 a first detent assembly to selectively isolate said potential energy source from said final controlled element; 
 a second detent assembly selectively operable independently of said first potential energy source, said second detent assembly, when selectively defeated, defeats said first detent assembly to allow said first potential energy source to move said final controlled element; 
 said first detent assembly comprises an actuating member connected to said final controlled element, said actuating member located between said first potential energy source and at least one dog, said dog having a radially extended position that prevents movement of said actuating member by said first potential energy source; 
 said dog is retained in said radially extended position by said second detent assembly. 
 
     
     
       6. The assembly of  claim 5 , wherein:
 said second detent assembly initially disposed between said mandrel and said at least one dog to support said at least one dog in said first position of said at least one dog, whereupon relative movement of said second detent assembly with respect to said at least one dog allows said at least one dog to move to a second position allowing said first potential energy source to move said actuating member and final controlled element. 
 
     
     
       7. The assembly of  claim 6 , wherein:
 said second detent assembly initially positioned radially between said mandrel and said at least one dog to allow said dog to block movement of said actuating member; 
 whereupon axial movement of said second detent assembly allows said at least one dog to move radially toward said mandrel into a second position and out of a path of movement of said actuating member. 
 
     
     
       8. The assembly of  claim 7 , wherein:
 said actuating member moves over said at least one dog when said dog is in said second position. 
 
     
     
       9. The assembly of  claim 7 , wherein:
 said at least one dog comprises at least one cantilevered end; 
 said second detent assembly comprises at least one elongated member selectively supporting said cantilevered end until a slot on said elongated member aligns with said cantilevered end allowing said at least one dog to move toward said mandrel. 
 
     
     
       10. The assembly of  claim 9 , wherein:
 said actuating member comprising a leading tapered surface to cam said at least one dog into a mandrel slot when said slot on said at least one elongated member aligns with said cantilevered end of said at least one dog. 
 
     
     
       11. The assembly of  claim 10 , wherein:
 said at least one dog comprises a plurality of dogs each having opposed cantilevered ends; 
 said at least one elongated member comprises a plurality of spaced elongated members extending from a base ring, said elongated members located on opposed sides of said dogs and selectively engaging said opposed cantilevered ends. 
 
     
     
       12. The assembly of  claim 11 , wherein:
 said base ring is biased by a second potential energy source for selective movement in an opposed direction than said actuating member. 
 
     
     
       13. The assembly of  claim 12 , wherein:
 said second potential energy source comprises at least one spring that is weaker than another at least one spring that comprises said first potential energy source. 
 
     
     
       14. The assembly of  claim 9 , wherein:
 said at least one elongated member selectively prevented from moving axially when biased by a second potential energy source by a radially movable member that abuts said mandrel. 
 
     
     
       15. The assembly of  claim 14 , wherein:
 said radially movable member is indirectly actuated to move radially with respect to said mandrel to allow said elongated member to move under bias from said second potential energy source. 
 
     
     
       16. The assembly of  claim 15 , wherein:
 said radially movable member is actuated with a magnetic field applied from within said mandrel. 
 
     
     
       17. The assembly of  claim 16 , wherein:
 said second potential energy source comprises at least one release spring that is weaker than at least one actuating spring that comprises said first potential energy source. 
 
     
     
       18. The assembly of  claim 17 , wherein:
 said at least one release spring creating a frictional resistance to radial movement of said radially movable member, said frictional resistance is overcome by said magnetic field. 
 
     
     
       19. The assembly of  claim 18 , wherein:
 said actuating member is biased by said actuating spring in an opposite direction than said release spring biases said at least one elongated member. 
 
     
     
       20. The assembly of  claim 19 , wherein:
 initial movement of said at least one elongated member allows said dog to move away from said actuator so that said actuating spring can move said actuator and said final controlled element.